The disclosure generally relates to a transmitter circuit and, more particularly, to a transmitter circuit capable of measuring transmitter-side image rejection ratio.
Gain mismatch and/or phase mismatch between an in-phase signal and a quadrature signal in a transmitter circuit of a wireless communication device, i.e., the so-called I/Q mismatch, can be measured based on the image rejection ratio of the transmitter circuit. Conventionally, the image rejection ratio of the transmitter circuit is typically measured by utilizing an external apparatus, such as a spectrum analyzer, to inspect the signal at the transmitter side of the transmitter circuit.
However, since the conventional measurement approach requires the use of the spectrum analyzer or other external apparatuses, the efficiency and convenience of measurement are not ideal. In particular, when there is a great amount of transmitter circuits to be measured, it would consume considerable labors and time to respectively couple these transmitter circuits one after another with the spectrum analyzer or other external apparatuses.